Current state of automatic footnotes. (issue4580041)

[mtsolo]

Reviewers: ,

Message:
Hey all,

Here is the current state of automatic footnotes.  Some things to note:

(1)  It nixes the two-pass algorithm to account for annotation width but
provides enough information to create a two (or many) pass algorithm
entirely from Scheme.  Said algorithm can go in the LSR and/or docs.

(2)  The "text" feature of FootnoteItem and FootnoteSpanner no longer
kludgily tacks on a stencil - it remains pure text.

Cheers,
MS

Description:
Current state of automatic footnotes.

Please review this at http://codereview.appspot.com/4580041/

Affected files:
  A input/regression/footnote-auto-numbering-page-reset.ly
  A input/regression/footnote-auto-numbering.ly
  M input/regression/footnote-break-visibility.ly
  M input/regression/footnote-spanner.ly
  M input/regression/footnote.ly
  M lily/align-interface.cc
  M lily/balloon.cc
  M lily/constrained-breaking.cc
  M lily/include/page-breaking.hh
  M lily/include/page-layout-problem.hh
  M lily/include/system.hh
  M lily/output-def-scheme.cc
  M lily/page-breaking.cc
  M lily/page-layout-problem.cc
  M lily/page-spacing.cc
  M lily/paper-book.cc
  M lily/paper-system.cc
  M lily/system.cc
  M ly/music-functions-init.ly
  M ly/paper-defaults-init.ly
  M scm/define-grobs.scm
  M scm/define-markup-commands.scm
  M scm/lily-library.scm
  M scm/output-lib.scm